POLYAMINE INVOLVEMENT IN MAMMARY CARCINOGENESIS

描述：本项目将重点研究多胺的活化作用 生物合成和MAPK信号级联（通过致癌ras或 HER-2neu）在乳腺癌发展中的作用。 这些研究的基本原理是 （1）Manni博士的初步数据表明， 多胺在乳腺癌发生中的协同作用; ras信号和多胺之间的恶性肿瘤模型 转换，（3）初步数据显示之间的协同性 HER-2neu信号和多胺在乳腺癌发生中的作用; 申请人最近发现ODC过表达增加MAPK 乳腺上皮细胞中的活性。 此外，研究者将 测试功能性雌激素受体表达的重要性 ras/HER-2neu和/或多胺介导的乳腺癌发生。 他将 在自发永生化但非致瘤性的 MCF-10A和HMT-3522人乳腺上皮细胞系。 具体而言：（1） 他将确定鸟氨酸脱羧酶过度表达的影响 (ODC)（多胺生物合成中的第一限速酶） 单独地和与MAPK级联的激活（通过 ras或HER 2-neu）对体外和体内转化特征的影响。 (2)他将确定MAPK级联途径在介导 多胺和/或ras/HER-2neu介导的影响，通过转染我们的细胞 具有几种激酶的组成型活性和显性失活突变体 属于该信号级联（例如Raf-1、MEK、ERK-1、ERK-2）。 （三） 他将利用最近一代ER转染的MCF-10A 和表达功能性ER的HMT-3522细胞系，以测试可能的 恶性肿瘤中激素和致癌信号之间的协同作用 人乳腺上皮细胞的转化。 (4)他将评估 雌激素受体与雌激素受体之间在转录水平上的“串扰” 途径和ras/HER-2neu/多胺介导的信号传导，因为它涉及 乳腺癌发生 预计拟议的 实验将提供新的见解的机制， 雌激素与经典致癌信号协同诱导 正常人乳腺上皮细胞的转化。

DESCRIPTION: This project will focus on the role of activation of polyamine biosynthesis and MAPK signaling cascade (by either oncogenic ras or HER-2neu) in breast cancer development. The rationale for these studies is provided by (1) Dr. Manni's preliminary data suggestive of a role for polyamines in mammary carcinogenesis, (2) the demonstrated cooperativity between ras signalling and polyamines in several models of malignant transformation, (3) the preliminary data showing cooperativity between HER-2neu signaling and polyamines in mammary carcinogenesis, and (4) the recent finding by the applicant that ODC overexpression increases MAPK activity in mammary epithelial cells. Furthermore, the investigator will test the importance of expression of a functional estrogen receptor in ras/HER-2neu and/or polyamine-mediated mammary carcinogenesis. He will conduct experiments in the spontaneously immortalized but non-tumorigenic MCF-10A and HMT-3522 human breast epithelial cell lines. Specifically: (1) He will determine the influence of overexpression of ornithine decarboxylase (ODC) (the first rate-limiting enzyme in polyamine biosynthesis) individually and in combination with activation of the MAPK cascade (by either ras or HER2-neu) on in vitro and in vivo features of transformation. (2) He will determine the role of the MAPK cascade pathway in mediating polyamines and/or ras/HER-2neu mediated effects by transfecting our cells with constitutively active and dominant negative mutants of several kinases belonging to this signalling cascade (e.g. Raf-1, MEK, ERK-1, ERK-2). (3) He will take advantage of the recent generation of ER transfected MCF-10A and HMT-3522 cell lines which express a functional ER to test the possible cooperativity between hormonal and oncogenic signals in the malignant transformation of human breast epithelial cells. (4) He will evaluate the "cross-talk" at the transcriptional level between the estrogen receptor pathway and ras/HER-2neu/ polyamine-mediated signaling as it relates to mammary carcinogenesis. It is anticipated that the results of the proposed experiments will provide new insights into the mechanisms subserving the cooperativity between estrogens and classic oncogenic signals in inducing transformation of normal human breast epithelial cells.